1. Field of the Invention
The present invention generally relates to a LCD technology field, and more particularly to a driver of promoting pixel charging ability of a thin film transistor and a method thereof.
2. Description of Prior Art
With the development of technology, the Liquid Crystal Display (LCD) has become the major product of displays nowadays. Thin film transistor-Liquid Crystal Display (TFT-LCD) is one of the active matrix liquid crystal display (AM-LCD). Generally, the metal-oxide-semiconductor field-effect transistor (MOS-FET) is employed as a charge element in the TFT-LCD panel. The running condition of the existing thin film transistors is: Vgh is 23V. The threshold voltage Vt is 1V. As considering a general data driving voltage 0V-14V, the largest charge and discharge voltage difference Vds is 14V (voltage difference between positive polarity voltage and negative polarity voltage). The voltage Vds□Vgs−Vt. Regarding the I-V Property of the thin film transistor, the thin film transistor is operated in the linear region. The current Id is relevant with the voltage difference of the polarity switching. Put differently, the current Id is in direct proportion to the voltage difference Vds (Id∞(Vgs−Vt)Vds) and the specific formula is introduced below:
      I    DS    ≈            μ      eff        ⁢    ζ    ⁢                  ⁢          C      i              α        -        1              ⁢          W      L        ⁢                  (                              V            GS                    -                      V            T                          )                    α        -        1              ⁢          V      DS      
However, the aforesaid charge method may increase the RC loading. Then, the signal distortion result in under charge.
For solving such issues, the product design in prior art requires the sacrifice of the aperture ratio (the higher the aperture ratio is, the brighter the whole screen becomes) to utilize wider metal line width to reduce the RC (current-limiting resistor) loading or manufacturing TFT element with 4PEP (Photo Etching Process, using the photoresist) to promote the phenomenon of under charge. However, such design results in over low aperture ratio and influence the brightness of the whole screen. The transmittance of the product and the processes are also tremendously influenced.
Consequently, there is a need to develop a driver of promoting pixel charging ability of a thin film transistor and a method thereof to solve the drawbacks of prior art.